What the word machines in field

Introduction

Among
all types of agricultural implements, field machinery is of sure
priority in the farm market. In this way, technical innovations and
basic requirements here are to be discussed at length in this Unit.

Exercise 1

The
following words will be of use for you, especially when mastering the
materials of this Unit. Study both their oral and written forms.

1. dealer
   — торговый
   агент;

2. estate
   — усадьба;

3. overhead
   costs
   — накладные
   расходы;

4. labour
   costs
   — трудовые
   затраты;

5. to
   wear out — изнашивать(ся);

6. complete
   overhaul
   — капитальный
   ремонт;

7. to
   eliminate — уничтожать;

8. range
   — диапазон;

9. continuous
   — продолжительный,
   длительный;

10. property
    — собственность;

11. to
    complete
    — завершить,
    полностью выполнить

12. capacity
    — мощность
    (букв.
    — способность);

13. substantial
    — значительный;

14. maintain
    — технически
    обслуживать (букв.
    — поддерживать);

15. adjust
    — налаживать,
    приспосабливать;

16. repair
    — ремонтировать
    (осуществлять текущий ремонт);

17. to
    manage
    — управлять,
    осуществлять руководство;

18. proper
    — соответствующий,
    подходящий.

Exercise 2

Consult
the textbook and other reference materials you have at your disposal,
in order to repeat the formation, use and Russian translation of
Participle
I
constructions
(as a part of the predicate (an element of the Tense-Aspect form),
and in the function of definition in the sentence, etc.).

Grammar Notes: 1) A specific feature of Participle I is the following: it is always employed to denote a certain continuity or an action in process. 2) In a sentence, Participle I can be used as an attribute, an adverbial modifier, a subject or an object, and even as a part of a complex predicate (including the Continuos forms), or in such grammar phenomena as the Complex Object or the Independent Participle Construction.

Now,
study-read the following text, paying attention to the meanings of
the sentences containing Participle I-forms.

Text 5

A
wide range of tractors and implements
in America are available
from local farm machinery dealers. Most of the larger machines and
equipment
sold are manufactured
in the USA, while many of the smaller tractors — particularly diesel
ones
— are imported
from abroad, mostly
from Western Europe. Garden tractors are designed
primarily
for light estate
duty
and are not intended
for continuous heavy services.

It
is important to manage
machine properly. This includes planning the use of machinery for
timely
and productive
operations,
selecting proper
types and sizes, replacing
worn-out machinery at the right time. Improvements in farm machinery
are continually being made to increase their efficiency and to reduce
manual labour. These changes are coming so rapidly that innovations
may become common
practice
in a remarkably
short time.

Most
manipulations involve
several different crops with specific tillage, planning, pest
control and harvesting requirements.
Ideally, each crop should have its own set
of specialized implements to produce maximum yields.
More equipment in turn means higher overhead costs. Lack of adequate
equipment can delay getting
crops planted or harvested in time, reducing yields and product
quality.
Thus, the most crucial
progress,
now seen on many farms, is in combining various operations and
universal plant-species treatments in one machine. For instance, this
has been done in the combine for harvesting and threshing wheat and
other grains,
and in the grain drill that in one trip
over the field
does the work of preparing the seedbed, planting seed and applying
fertilizers and herbicides.

Among
the advantages of farm mechanization we might mention first, that the
production and income per person engaged in farming have been
markedly increased, that farm tasks can be done more rapidly and with
better quality when weather and soil conditions are the least
favourable, and, then, modern machinery enables crops to be planted,
cultivated and harvested in a considerably shorter time than in the
past, and the same is largely true in case of livestock production
operations.

If
we turn to the disadvantages of the replacement of manual labour with
machines and automated equipment now, we will surely note the
following factors. First of all, farmers must have more capital in
disposal to be engaged in farming because of the inevitable need in
large investments in farm machines and other equipment. Second,
farmers must have a larger and more stable income to have electricity
and fuel bills paid. Finally, small farms are destined to
disappearing, for larger ones are of apparent advantage today.

Using
larger machines reduces
labour costs since they complete the job faster.
But while larger tractors can cover more acreage
than smaller ones,
they also have higher overhead
costs.
Smaller tractors have less capacity and may cause
delay
in key
field operations, resulting
in
a lower crop
yields. Some of the time lost
in doing field work cannot be cut,
prevented or eliminated. Other lost time can be substantially reduced
by careful planning
and good management.

Keeping
farm machinery in top mechanical condition is one of the best ways
to improve
field working efficiency.
Machines should be technically maintained properly,
i.e. serviced
regularly and adjusted correctly.
Neglecting this can result in expensive
repair procedures
or cause complete overhauls.

Exercise
3

1. Guess
   the meaning of the terms and word-combinations underlined in the
   text, through analysis of their position and the context they appear
   in;

1. now, look them up in a
   dictionary;

1. find out the logic behind
   their use in the given situations;

2. provide as many their
   synonyms, as you can think of;

3. make
   your own sentences with them;

4. Now,
   translate the entire text (with a good dictionary).

Exercise
4

1. Scan
   the text one more time, in order to find and copy to your notebook
   its parts which answer the questions coming next, asked by the Head
   of your Mechanical department who gave you this text for
   consideration:

1. Какие
   условия являются идеальными для
   выращивания сельхозкультур?

2. Какие трактора
   импортируют США?

3. К чему ведет
   недостаток оборудования в сельском
   хозяйстве?

4. Какие факторы
   увеличивают накладные расходы?

5. Что может привести
   к необходимости капитального ремонта
   оборудования?

1. Basing
   on the text, and recalling your own agricultural experience and
   knowledge, provide extended responds to the questions given below.

When presenting your answers,
resort to the practical speech combinations from the following list.

Соседние файлы в предмете Английский язык

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Text 24. Mechanization in crop production

Tillage practices vary with soil and climatic conditions and the crop that is to be grown. Tillage includes plowing, harrowing and rolling the soil. There are some purposes of tilling the soil. They are to improve the aera­tion and temperature conditions, to produce a firm soil and to control weeds. Different types of plows, harrows and rollers are now available to till the soil.

Seed should be sown in a firm, moist soil and covered at a proper depth to germinate rapidly and uniformly. Many various types of grain drills and planters have been developed to suit varying farm requirements. Some modern drills are equipped with attachments for seeding legume and grass seed and for spreading fertilizers. So, seed can be sown and fertilizer spread in one operation. Fertilizers can also be broadcast before planting. Recently attachments have been added to planters for applying insecticides and herbicides to the soil.

Harvesting crops is the final field operation. Combines that harvest and thresh small grains and some other crops have displaced most threshing machines or threshers. For harvesting to be successful, one should grow a variety that is adapted to mechanical harvesting. The plants should be of uniform height and should mature uniformly. Root crops and potatoes are harvested with root lifters and potato diggers respectively.

Learn the words.

aeration — аэрация (почвы)

attachment – приспособление

to control – уничтожать, бороться

cover seed – заделывать семена

to equip – оборудовать, оснащать

moist – влажный

potato digger – картофелекопалка

roller – каток

root lifter – уборочная машина для корнеплодов

to spread – разбрасывать

to thresh – молотить

thresher – молотилка

uniform – однородный, одинаковый

1. Answer the following questions:

1. What operations does tillage include?

2. What machines are used in tilling the soil?

3. What are some drills equipped with?

4. What is the final field operation?

5. What machines are used in root crop and potato har­vesting?

2. Complete the sentences of the following words and phrase:

1. tillage practices; by applying; proper; can be; improved; soils. 2. a fine oil; are used; harrows; to produce. 3. seed; in; a moist soil; rapidly, germinates. 4. in one operation; harvest; thresh; and; combines.

3. Прочитайте и переведите предложения, в которых говорится:

а) о факторах, которые влияют на выбор приёмов обработки почвы;

б) о целях обработки почвы;

в) об условиях быстрого прорастания семян;

г) о том, как можно применять гербициды;

д) об использовании комбайнов.

Read and translate the text:

Text 25. Equipment for planting cereals

Broadcasting by hand was used in the USA as the main method of planting wheat and other small grains about a century ago. Later various types of grain drills and seeders have been developed.

Today, with a 12-foot (фут = 30,5 cm) tractor-drawn drill one person can seed 50 to 60 acres per day at a proper rate and at uniform depth. To in­crease the daily acreage two or more of these drills are combined together.

Planting

The warm-season cereals are grown in tropical lowlands year-round and in temperate climates during the frost-free season. Rice is commonly grown in flooded fields, though some strains are grown on dry land. Other warm climate cereals, such as sorghum, are adapted to arid conditions.

Cool-season cereals are well-adapted to temperate climates. Most varieties of a particular species are either winter or spring types. Winter varieties are sown in the autumn, germinate and grow vegetative, then become dormant during winter. They resume growing in the springtime and mature in late spring or early summer. This cultivation system makes optimal use of water and frees the land for another crop early in the growing season.

Winter varieties do not flower until springtime because they require vernalization: exposure to low temperature for a genetically determined length of time. Where winters are too warm for vernalization or exceed the hardiness of the crop (which varies by species and variety), farmers grow spring varieties. Spring cereals are planted in early springtime and mature later that same summer, without vernalization. Spring cereals typically require more irrigation and yield less than winter cereals.

Learn the words.

the wheat – пшеница

a drill – сеялка

an acreage – площадь

a broadcasting – посев

a lowland – низменность

flooded fields – затопленные поля

sorghum – сорго

the varieties – сорта

to become dormant during winter – становиться пассивным зимой

to resume – возобновлять

to mature – созревать

to require vernalization – требовать яровизации

an exposure – воздействие

the hardiness of the crop – морозостойкость культур

an irrigation – полив

winter cereals – озимые зерновые

1. Answer the following questions:

1) What is the main method of planting grain a century ago?

2) What equipment is used for planting crops?
3) What kind of cereal do you know?
4) Are sown winter varieties in the autumn?
5) When are planted spring cereals?
6) What kind of cereals require more irrigation?
2. Complete the sentences:

1. Most varieties of a particular species are either winter or spring _____.
2. __________the daily acreage two or more of these drills are combined together.
3. Spring _______ typically require more irrigation.
4. Winter varieties are sown in__________.
5. __________makes optimal use of water and frees the land for another crop early in the growing season.
6. __________ are planted in early springtime.
7. Rice is commonly grown in___________, though some strains are grown on dry land.
8. Where winters are _________for vernalization, farmers grow spring varieties.

______________________________________________________________

To in­crease , spring cereals, too warm , the autumn, types, flooded fields, cereals, cultivation system.

3. Write 3 forms of verbs:

To grow, to become, to have, to adapt, to make, to plant.

Read and translate the text:

Text 26. Importance of machinery and energy in agriculture

More and more machines are used on farms today replacing hand labour and increasing labour productivity. With machines and power avail­able farmers not only can do more work and do it more economically, but (hey can do higher-quality work and the work may be finished in a shorter and more favourable time.

Machines that are used for crop production include those that till the soil, plant the crops, perform various cultural practices during the growing season and harvest the crops.

Many machines are known to be powered by tractors. Implements such as plows, cultivators and planters may be mounted on a tractor or they may be pulled by a tractor.

However, an increasing number of farm machines are now self-propelled. These machines are grain combine harvesters, cotton pickers, forage harvesters, and many other specialized farm machines.

Machines that do not require mobility are usually powered with electric motors. Such machines include silage unloaders, livestock feeding equip­ment and milking machines.

Farm machines we use today are quite different from those the farmers used two or even one decade ago. The tractors, tractor-drawn planters and drills were smaller and less productive. They could plant less acres per day than the machines do now.

Learn the words.

combine harvester- уборочный комбайн

cotton picker — хлопкоуборочная машина

cultivator – культиватор

drill – рядовая сеялка

equipment – оборудование

hand labour – ручной труд

implement – орудие

milking machine – доильный аппарат

mount – навешивать

planter – посадочная машина, сажалка

plow – плуг

power – энергия, приводить в движение (глаг.)

pull – тянуть

self- propelled – самоходный

silage – unloader – разгрузочная машина для силоса

to till – обрабатывать почву

tractor- drawn – на тракторной тяге

1. Complete the sentences:

1. Plows and various cultivators are used
2. Self-propelled machines are those that
3. Silage unloader and milking machines are powered
4. Cereals are planted

________________________________________

a, are not powered by tractors.

b. with tractor-drawn drills.

c. to till the soil.

d. with electricity.

2. Переведите предложения, в которых говорится:

1. о том, что машины выполняют работу экономически более выгодно;
2. о машинах, приводимых в движение тракторами;
3. о сельхоз. Машинах в прошлом и будущем.

3. Answer the following questions:

1. Do machines make labour more productive?
2. Can machines do work in a shorter time?
3. What machines are mounted on a tractor?
4. What self-propelled machines do you know?
5. Are milking machines pow­ered with electricity?
6. What do modern machines differ in?

ПРИЛОЖЕНИЕ 1

АНГЛО-РУССКИЙ СЛОВАРЬ ТЕРМИНОВ

Сокращения

a – adjective – прилагательное

adv – adverb – наречие

n – noun – существительное

pl – plural – множественное число

v – verb — глагол

adaptability n — приспособляемость

aeration n — аэрация (почвы)

affect v – влиять (на что-либо)

alfalfa n – люцерна

apply v – применять, вносить

attachment n — приспособление

automation n — автоматизация

bedding n – подстилка

body n – орган

breeder n – селекционер, животновод

broadcast v – разбрасывать (семена и др.)

carbohydrate n — углевод

care n – уход, забота; v заботиться

closely adv – тесно

coarse a – крупный (о семенах)

common a – обычный, распространённый

compaction n- уплотнение

concentrate n— концентрированный корм, концентрат

condition n- состояние, кондиция

control n – борьба, контроль; v бороться, контролировать

cost n – стоимость, себестоимость; pl затраты, издержки

cover v – заделывать(семена)

cowshed n – хлев, коровник

crop n — (c.-x.) культура

crossbreeding n — кросс-бридинг (скрещивание неродственных особей)

cultivation n— выращивание, возделывание; обработка

cutter n – резальная машина

dairy a – молочный

depreciation n— амортизация, износ

digestible a – перевариваемый, усвояемый

digestion n — переваривание, усвоение

digger n — копалка

draft a — тягловый, рабочий (скот)

dual-purpose (cattle) a— мясо-молочный скот

economics n – экономика

economy n – экономика, хозяйство

efficiency n – эффективность, производительность

electronic a – электронный

employment n— занятость

farming n – ведение хозяйства, земледелие

fibre n – клетчатка

fibrous a — мочковатый (о корне)

fine a – мелкокомковатый (о почве), мелкий (о семенах)

firm a – уплотнённый, осевший (о почве)

flock n – отара

gain v – прибавлять в весе

germination n – прорастание

grass n – злак, трава

grinder n – дробилка

grower n – фермер, колхозник; производитель

herbicide n – гербицид

high-yielding a – высокоурожайный, высокоудойный

inbreeding n— инбридинг (родственное спаривание)

indication n — показатель

indigestible a – непериваримый

insecticide n — инсектицид

kind n — вид

labour-consuming a — трудоёмкий

legume n – бобовое растение

lifter n — подъёмное приспособление

maintenance n – поддержание, сохранение

management n –содержание, управление

markedly adv заметно

marketing n – реализация, сбыт

mellow a – рыхлый, спелый

mobility n — побвижность, мобильность

mount v — навешивать

nutrient n – питательное вещество; а питательный

nutritional а — пищевой

overfeed v — перекармливать

photosynthesis n — фотосинтез

picker n – уборочная машина

planter n – посадочная машина

power n – энергия; v приводить в движение

practice n — приём

production n – возделывание, производство

productivity n – производительность, продуктивность

profitability n – рентабельность, прибыльность

profitable a – рентабельный, прибыльный

purebred a – чистопородный

rainfall f n – осадки

remove v – выносить (питательные вещества из почвы)

robotization n — роботизация

roll v — прикатывать (почву)

roller n — каток

roughage n – грубый корм

seedbed n – пашня

self-propelled a — самоходный

set v – устанавливать, налаживать

sheep-pen n – овчарня, загон для овец

sire n – производитель (о животных)

soybeans n — соя

spread v — разбрасывать

stand n – всходы, травостой, стеблестой

supplement n – добавка

tap a — стержневой (о корне)

technology n – технология

tractor-drawn a – на тракторной тяге

tuber n — клубень

underfeed v— недокармливать

unloader n – разгрузочная машина

utilization n — использование

variety n – сорт

yield n – урожай, надой (молока)

ЛИТЕРАТУРА

1. Г.В. Маслова — Пособие для сельскохозяйственных техникумов «Английский язык», Москва, 2001
2. Е.Н. Комарова — Английский язык для специальностей «Зоотехния» и «Ветеринария» , — М., 2008
3. http://www.englisharticles.info/2010/10/14/farming-mechanization/
4. http://www.gov.pe.ca/af/agweb/index.php3?number=70742

РЕЦЕНЗИЯ

на учебное пособие по дисциплине
«Английский язык»
для студентов отделения механизации сельского хозяйства
Автор: Кондалова И.А.

Учебное пособие составлено в соответствии с государственными требованиями к минимуму содержания и уровню подготовки студентов, рассмотрено и одобрено Цикловой методической комиссией общих гуманитарных и социально- экономических дисциплин.

Пособие состоит из 26 текстов по специальности «Механизация сельского хозяйства». Цель –работа с аутентичными текстами; научить студентов извлекать информацию из текста Для достижения поставленной цели разработана система упражнений. Материалы данного пособия помогают формировать навыки ознакомительного чтения, на основе смысловых опор и фоновых знаний извлекать из текста необходимую информацию.

Данное учебное пособие может выполнять функции руководства по изучению предложенной дисциплины, как на занятиях, так и может быть использовано для самостоятельной работы студента. Пособие выступает средством обучения, с помощью которого осуществляется организация образовательного процесса.

Учебное пособие является результатом обобщения педагогического и методического багажа преподавателя по данной дисциплине и может быть интересно преподавателям предмета «Английский язык» и преподавателям гуманитарных дисциплин.

Рецензент: преподаватель высшей категории Никитина Н.С.

Подпись ______________

Рецензия

на учебное пособие по дисциплине
«Английский язык»
для студентов отделения механизации сельского хозяйства
Автор: Кондалова И.А

Пособие предназначено для студентов, изучающих английский язык по специальности «Механизация сельского хозяйства». Пособие имеет чёткую структуру, обусловленную учебным планом для студентов 2 и 3 курса.

Каждый текст – узкоспециализирован и связан с конкретной областью механизации сельского хозяйства. Объём и степень сложности текстов нарастают по мере изучения материала, однако соответствующие комментарии включают перевод новых и непонятных для студентов слов, что должно облегчить работу и снять языковые трудности. Кроме того каждый текст подкреплён языковым лексическим минимумом. В пособие включены лексические и грамматические упражнения.

Учебное пособие способствует формированию у студентов разнообразных грамматических умений и навыков, таких как чтение и говорение в сфере профессионального общения, на основе соответствующей лексики.

Данное учебное пособие может быть рекомендовано преподавателям предмета «Английский язык» и преподавателям гуманитарных дисциплин.

Text 1. Farm machines

Every collective farm has various types of machines that plow the soil, plant the seeds, cultivate the plants, harvest the crops and transport the products harvested.

Soviet collective farmers use tractors (in terms of 15 horsepower units), lorries, different drills, planters and harvesters. At present nearly every branch of agronomy uses specialized harvesters. Thus, we find grain combine harvesters, corn pickers, cotton pickers, tea pickers, fruit pickers, tomato harvesters. For harvesting root and tuber crops there exist various diggers such as potato diggers, carrot diggers, sugar beet diggers, onion diggers, etc.

Learn the words.

a lorry- грузовик

in terms – в пересчёте

the tubers – клубни

a digger – экскаватор

an onion – лук

1. Answer the following questions:

1. What kinds of farm machines do you know?

2. What belongs to the specialized harvesters?

3. Exist various diggers for harvesting root and tuber crops?

2. Complete the sentences:  

a) Every branch of agronomy uses ____________.

b) There are various diggers such as______________.

c) ___________ has various types of machines.

d) ______________ use tractors, lorries, different drills, planters and harvesters.

………………………………………………………………………………..

potato diggers, carrot diggers; every collective farm; specialized harvesters; collective farmers.

3. Find English equivalents.

Используются различные экскаваторы, транспортировка выращенной продукции, в настоящее время, отрасли агрономии, сбор урожая.

4. Make singular from plural:

Types, diggers, pickers, harvesters, seeds, plants, lorries, drills.

Text 2. Harvesting Machinery

Harvesting machinery or equipment is a mechanical device used for harvesting. There are several types of harvesting machines which are generally classified by crop. Reapers are used for cutting cereal grains, threshers for separating the seed from the plant; whereas corn or maize harvesting is performed by employing a specially designed mechanical device ‘ mechanical corn pickers. ‘ A typical harvesting machine comprises of a traveling part, a reaping part, and a baler part.

Harvesting machines are also used for controlling the production of weeds. Machines like field choppers, balers, mowers, crushers and windrowers are the common examples of this category. A forage harvester is used for cutting and chopping of almost all silage crops.                                                                                                                   

    Types of Harvesting Machinery
Following is a brief description of major harvesting machines used all around the globe:

• Crop Harvesting Machine: The mechanical device which harvests forage crops cultivated in upland/paddy field and forms roll bale simultaneously was developed, is termed as crop harvesting machinery. It comprises of traveling, reaping and a baler part.

· Grain Harvesting Machine: This machine is used to harvest grains, the edible brans or fruit seeds of a cereal crop.

• Root crop Harvesting Machine: Traditionally root crops are harvested with diggers and digger-pickers. Now a days, several machines are available in the market. Modern sugar-beet harvester is one of the most popular examples of the root crop harvesting machine.
• Threshers: Threshers or threshing machine is used for the separation of grain from stalks and husks.
• Vegetable Harvesting Machine: Nowadays, machines are also available for the harvesting of vegetables. These ‘vegetable harvesting machines’, are quite common among the global vegetable farmers. Tomato harvesting machine is the most common example of this.

This article is about devices designed to perform tasks. For other uses, see Machine (disambiguation).

A machine is a physical system using power to apply forces and control movement to perform an action. The term is commonly applied to artificial devices, such as those employing engines or motors, but also to natural biological macromolecules, such as molecular machines. Machines can be driven by animals and people, by natural forces such as wind and water, and by chemical, thermal, or electrical power, and include a system of mechanisms that shape the actuator input to achieve a specific application of output forces and movement. They can also include computers and sensors that monitor performance and plan movement, often called mechanical systems.

Renaissance natural philosophers identified six simple machines which were the elementary devices that put a load into motion, and calculated the ratio of output force to input force, known today as mechanical advantage.^[1]

Modern machines are complex systems that consist of structural elements, mechanisms and control components and include interfaces for convenient use. Examples include: a wide range of vehicles, such as trains, automobiles, boats and airplanes; appliances in the home and office, including computers, building air handling and water handling systems; as well as farm machinery, machine tools and factory automation systems and robots.

Etymology[edit]

The English word machine comes through Middle French from Latin machina,^[2] which in turn derives from the Greek (Doric μαχανά makhana, Ionic μηχανή mekhane ‘contrivance, machine, engine’,^[3] a derivation from μῆχος mekhos ‘means, expedient, remedy’^[4]).^[5] The word mechanical (Greek: μηχανικός) comes from the same Greek roots. A wider meaning of ‘fabric, structure’ is found in classical Latin, but not in Greek usage. This meaning is found in late medieval French, and is adopted from the French into English in the mid-16th century.

In the 17th century, the word machine could also mean a scheme or plot, a meaning now expressed by the derived machination. The modern meaning develops out of specialized application of the term to stage engines used in theater and to military siege engines, both in the late 16th and early 17th centuries. The OED traces the formal, modern meaning to John Harris’ Lexicon Technicum (1704), which has:

Machine, or Engine, in Mechanicks, is whatsoever hath Force sufficient either to raise or stop the Motion of a Body. Simple Machines are commonly reckoned to be Six in Number, viz. the Ballance, Leaver, Pulley, Wheel, Wedge, and Screw. Compound Machines, or Engines, are innumerable.

The word engine used as a (near-) synonym both by Harris and in later language derives ultimately (via Old French) from Latin ingenium ‘ingenuity, an invention’.

History[edit]

The hand axe, made by chipping flint to form a wedge, in the hands of a human transforms force and movement of the tool into a transverse splitting forces and movement of the workpiece. The hand axe is the first example of a wedge, the oldest of the six classic simple machines, from which most machines are based. The second oldest simple machine was the inclined plane (ramp),^[6] which has been used since prehistoric times to move heavy objects.^[7][8]

The other four simple machines were invented in the ancient Near East.^[9] The wheel, along with the wheel and axle mechanism, was invented in Mesopotamia (modern Iraq) during the 5th millennium BC.^[10] The lever mechanism first appeared around 5,000 years ago in the Near East, where it was used in a simple balance scale,^[11] and to move large objects in ancient Egyptian technology.^[12] The lever was also used in the shadoof water-lifting device, the first crane machine, which appeared in Mesopotamia circa 3000 BC,^[11] and then in ancient Egyptian technology circa 2000 BC.^[13] The earliest evidence of pulleys date back to Mesopotamia in the early 2nd millennium BC,^[14] and ancient Egypt during the Twelfth Dynasty (1991-1802 BC).^[15] The screw, the last of the simple machines to be invented,^[16] first appeared in Mesopotamia during the Neo-Assyrian period (911-609) BC.^[17] The Egyptian pyramids were built using three of the six simple machines, the inclined plane, the wedge, and the lever.^[18]

Three of the simple machines were studied and described by Greek philosopher Archimedes around the 3rd century BC: the lever, pulley and screw.^[19][20] Archimedes discovered the principle of mechanical advantage in the lever.^[21] Later Greek philosophers defined the classic five simple machines (excluding the inclined plane) and were able to roughly calculate their mechanical advantage.^[1] Heron of Alexandria (ca. 10–75 AD) in his work Mechanics lists five mechanisms that can «set a load in motion»; lever, windlass, pulley, wedge, and screw,^[20] and describes their fabrication and uses.^[22] However, the Greeks’ understanding was limited to statics (the balance of forces) and did not include dynamics (the tradeoff between force and distance) or the concept of work.^{[citation needed]}

The earliest practical water-powered machines, the water wheel and watermill, first appeared in the Persian Empire, in what are now Iraq and Iran, by the early 4th century BC.^[23] The earliest practical wind-powered machines, the windmill and wind pump, first appeared in the Muslim world during the Islamic Golden Age, in what are now Iran, Afghanistan, and Pakistan, by the 9th century AD.^{[24][25][26][27]} The earliest practical steam-powered machine was a steam jack driven by a steam turbine, described in 1551 by Taqi al-Din Muhammad ibn Ma’ruf in Ottoman Egypt.^[28][29]

The cotton gin was invented in India by the 6th century AD,^[30] and the spinning wheel was invented in the Islamic world by the early 11th century,^[31] both of which were fundamental to the growth of the cotton industry. The spinning wheel was also a precursor to the spinning jenny, which was a key development during the early Industrial Revolution in the 18th century.^[32] The crankshaft and camshaft were invented by Al-Jazari in Northern Mesopotamia circa 1206,^[33][34][35] and they later became central to modern machinery such as the steam engine, internal combustion engine and automatic controls.^[36]

The earliest programmable machines were developed in the Muslim world. A music sequencer, a programmable musical instrument, was the earliest type of programmable machine. The first music sequencer was an automated flute player invented by the Banu Musa brothers, described in their Book of Ingenious Devices, in the 9th century.^[37][38] In 1206, Al-Jazari invented programmable automata/robots. He described four automaton musicians, including drummers operated by a programmable drum machine, where they could be made to play different rhythms and different drum patterns.^[39]

During the Renaissance, the dynamics of the Mechanical Powers, as the simple machines were called, began to be studied from the standpoint of how much useful work they could perform, leading eventually to the new concept of mechanical work. In 1586 Flemish engineer Simon Stevin derived the mechanical advantage of the inclined plane, and it was included with the other simple machines. The complete dynamic theory of simple machines was worked out by Italian scientist Galileo Galilei in 1600 in Le Meccaniche («On Mechanics»).^[40][41] He was the first to understand that simple machines do not create energy, they merely transform it.^[40]

The classic rules of sliding friction in machines were discovered by Leonardo da Vinci (1452–1519), but remained unpublished in his notebooks. They were rediscovered by Guillaume Amontons (1699) and were further developed by Charles-Augustin de Coulomb (1785).^[42]

James Watt patented his parallel motion linkage in 1782, which made the double acting steam engine practical.^[43] The Boulton and Watt steam engine and later designs powered steam locomotives, steam ships, and factories.

The Industrial Revolution was a period from 1750 to 1850 where changes in agriculture, manufacturing, mining, transportation, and technology had a profound effect on the social, economic and cultural conditions of the times. It began in the United Kingdom, then subsequently spread throughout Western Europe, North America, Japan, and eventually the rest of the world.

Starting in the later part of the 18th century, there began a transition in parts of Great Britain’s previously manual labour and draft-animal-based economy towards machine-based manufacturing. It started with the mechanisation of the textile industries, the development of iron-making techniques and the increased use of refined coal.^[44]

Simple machines[edit]

The idea that a machine can be decomposed into simple movable elements led Archimedes to define the lever, pulley and screw as simple machines. By the time of the Renaissance this list increased to include the wheel and axle, wedge and inclined plane. The modern approach to characterizing machines focusses on the components that allow movement, known as joints.

Wedge (hand axe): Perhaps the first example of a device designed to manage power is the hand axe, also called biface and Olorgesailie. A hand axe is made by chipping stone, generally flint, to form a bifacial edge, or wedge. A wedge is a simple machine that transforms lateral force and movement of the tool into a transverse splitting force and movement of the workpiece. The available power is limited by the effort of the person using the tool, but because power is the product of force and movement, the wedge amplifies the force by reducing the movement. This amplification, or mechanical advantage is the ratio of the input speed to output speed. For a wedge this is given by 1/tanα, where α is the tip angle. The faces of a wedge are modeled as straight lines to form a sliding or prismatic joint.

Lever: The lever is another important and simple device for managing power. This is a body that pivots on a fulcrum. Because the velocity of a point farther from the pivot is greater than the velocity of a point near the pivot, forces applied far from the pivot are amplified near the pivot by the associated decrease in speed. If a is the distance from the pivot to the point where the input force is applied and b is the distance to the point where the output force is applied, then a/b is the mechanical advantage of the lever. The fulcrum of a lever is modeled as a hinged or revolute joint.

Wheel: The wheel is an important early machine, such as the chariot. A wheel uses the law of the lever to reduce the force needed to overcome friction when pulling a load. To see this notice that the friction associated with pulling a load on the ground is approximately the same as the friction in a simple bearing that supports the load on the axle of a wheel. However, the wheel forms a lever that magnifies the pulling force so that it overcomes the frictional resistance in the bearing.

The classification of simple machines to provide a strategy for the design of new machines was developed by Franz Reuleaux, who collected and studied over 800 elementary machines.^[46] He recognized that the classical simple machines can be separated into the lever, pulley and wheel and axle that are formed by a body rotating about a hinge, and the inclined plane, wedge and screw that are similarly a block sliding on a flat surface.^[47]

Simple machines are elementary examples of kinematic chains or linkages that are used to model mechanical systems ranging from the steam engine to robot manipulators. The bearings that form the fulcrum of a lever and that allow the wheel and axle and pulleys to rotate are examples of a kinematic pair called a hinged joint. Similarly, the flat surface of an inclined plane and wedge are examples of the kinematic pair called a sliding joint. The screw is usually identified as its own kinematic pair called a helical joint.

This realization shows that it is the joints, or the connections that provide movement, that are the primary elements of a machine. Starting with four types of joints, the rotary joint, sliding joint, cam joint and gear joint, and related connections such as cables and belts, it is possible to understand a machine as an assembly of solid parts that connect these joints called a mechanism .^[48]

Two levers, or cranks, are combined into a planar four-bar linkage by attaching a link that connects the output of one crank to the input of another. Additional links can be attached to form a six-bar linkage or in series to form a robot.^[48]

Mechanical systems[edit]

A mechanical system manages power to accomplish a task that involves forces and movement. Modern machines are systems consisting of (i) a power source and actuators that generate forces and movement, (ii) a system of mechanisms that shape the actuator input to achieve a specific application of output forces and movement, (iii) a controller with sensors that compare the output to a performance goal and then directs the actuator input, and (iv) an interface to an operator consisting of levers, switches, and displays. This can be seen in Watt’s steam engine in which the power is provided by steam expanding to drive the piston. The walking beam, coupler and crank transform the linear movement of the piston into rotation of the output pulley. Finally, the pulley rotation drives the flyball governor which controls the valve for the steam input to the piston cylinder.

The adjective «mechanical» refers to skill in the practical application of an art or science, as well as relating to or caused by movement, physical forces, properties or agents such as is dealt with by mechanics.^[49] Similarly Merriam-Webster Dictionary^[50] defines «mechanical» as relating to machinery or tools.

Power flow through a machine provides a way to understand the performance of devices ranging from levers and gear trains to automobiles and robotic systems. The German mechanician Franz Reuleaux^[51] wrote, «a machine is a combination of resistant bodies so arranged that by their means the mechanical forces of nature can be compelled to do work accompanied by certain determinate motion.» Notice that forces and motion combine to define power.

More recently, Uicker et al.^[48] stated that a machine is «a device for applying power or changing its direction.»McCarthy and Soh^[52] describe a machine as a system that «generally consists of a power source and a mechanism for the controlled use of this power.»

Power sources[edit]

Human and animal effort were the original power sources for early machines.^{[citation needed]}

Waterwheel: Waterwheels appeared around the world around 300 BC to use flowing water to generate rotary motion, which was applied to milling grain, and powering lumber, machining and textile operations. Modern water turbines use water flowing through a dam to drive an electric generator.

Windmill: Early windmills captured wind power to generate rotary motion for milling operations. Modern wind turbines also drives a generator. This electricity in turn is used to drive motors forming the actuators of mechanical systems.

Engine: The word engine derives from «ingenuity» and originally referred to contrivances that may or may not be physical devices.^[53] A steam engine uses heat to boil water contained in a pressure vessel; the expanding steam drives a piston or a turbine. This principle can be seen in the aeolipile of Hero of Alexandria. This is called an external combustion engine.

An automobile engine is called an internal combustion engine because it burns fuel (an exothermic chemical reaction) inside a cylinder and uses the expanding gases to drive a piston. A jet engine uses a turbine to compress air which is burned with fuel so that it expands through a nozzle to provide thrust to an aircraft, and so is also an «internal combustion engine.» ^[54]

Power plant: The heat from coal and natural gas combustion in a boiler generates steam that drives a steam turbine to rotate an electric generator. A nuclear power plant uses heat from a nuclear reactor to generate steam and electric power. This power is distributed through a network of transmission lines for industrial and individual use.

Motors: Electric motors use either AC or DC electric current to generate rotational movement. Electric servomotors are the actuators for mechanical systems ranging from robotic systems to modern aircraft.

Fluid Power: Hydraulic and pneumatic systems use electrically driven pumps to drive water or air respectively into cylinders to power linear movement.

Electrochemical: Chemicals and materials can also be sources of power.^[55] They may chemically deplete or need re-charging, as is the case with batteries,^[56] or they may produce power without changing their state, which is the case for solar cells and thermoelectric generators.^[57][58] All of these, however, still require their energy to come from elsewhere. With batteries, it is the already existing chemical potential energy inside.^[56] In solar cells and thermoelectrics, the energy source is light and heat respectively.^[57][58]

Mechanisms[edit]

The mechanism of a mechanical system is assembled from components called machine elements. These elements provide structure for the system and control its movement.

The structural components are, generally, the frame members, bearings, splines, springs, seals, fasteners and covers. The shape, texture and color of covers provide a styling and operational interface between the mechanical system and its users.

The assemblies that control movement are also called «mechanisms.»^[51][59] Mechanisms are generally classified as gears and gear trains, which includes belt drives and chain drives, cam and follower mechanisms, and linkages, though there are other special mechanisms such as clamping linkages, indexing mechanisms, escapements and friction devices such as brakes and clutches.

The number of degrees of freedom of a mechanism, or its mobility, depends on the number of links and joints and the types of joints used to construct the mechanism. The general mobility of a mechanism is the difference between the unconstrained freedom of the links and the number of constraints imposed by the joints. It is described by the Chebychev-Grübler-Kutzbach criterion.

Gears and gear trains[edit]

The transmission of rotation between contacting toothed wheels can be traced back to the Antikythera mechanism of Greece and the south-pointing chariot of China. Illustrations by the renaissance scientist Georgius Agricola show gear trains with cylindrical teeth. The implementation of the involute tooth yielded a standard gear design that provides a constant speed ratio. Some important features of gears and gear trains are:

• The ratio of the pitch circles of mating gears defines the speed ratio and the mechanical advantage of the gear set.
• A planetary gear train provides high gear reduction in a compact package.
• It is possible to design gear teeth for gears that are non-circular, yet still transmit torque smoothly.
• The speed ratios of chain and belt drives are computed in the same way as gear ratios. See bicycle gearing.

Cam and follower mechanisms[edit]

A cam and follower is formed by the direct contact of two specially shaped links. The driving link is called the cam (also see cam shaft) and the link that is driven through the direct contact of their surfaces is called the follower. The shape of the contacting surfaces of the cam and follower determines the movement of the mechanism.

Linkages[edit]

A linkage is a collection of links connected by joints. Generally, the links are the structural elements and the joints allow movement. Perhaps the single most useful example is the planar four-bar linkage. However, there are many more special linkages:

• Watt’s linkage is a four-bar linkage that generates an approximate straight line. It was critical to the operation of his design for the steam engine. This linkage also appears in vehicle suspensions to prevent side-to-side movement of the body relative to the wheels. Also see the article Parallel motion.
• The success of Watt’s linkage lead to the design of similar approximate straight-line linkages, such as Hoeken’s linkage and Chebyshev’s linkage.
• The Peaucellier linkage generates a true straight-line output from a rotary input.
• The Sarrus linkage is a spatial linkage that generates straight-line movement from a rotary input.
• The Klann linkage and the Jansen linkage are recent inventions that provide interesting walking movements. They are respectively a six-bar and an eight-bar linkage.

Planar mechanism[edit]

A planar mechanism is a mechanical system that is constrained so the trajectories of points in all the bodies of the system lie on planes parallel to a ground plane. The rotational axes of hinged joints that connect the bodies in the system are perpendicular to this ground plane.

Spherical mechanism[edit]

A spherical mechanism is a mechanical system in which the bodies move in a way that the trajectories of points in the system lie on concentric spheres. The rotational axes of hinged joints that connect the bodies in the system pass through the center of these circle.

Spatial mechanism[edit]

A spatial mechanism is a mechanical system that has at least one body that moves in a way that its point trajectories are general space curves. The rotational axes of hinged joints that connect the bodies in the system form lines in space that do not intersect and have distinct common normals.

Flexure mechanisms[edit]

A flexure mechanism consists of a series of rigid bodies connected by compliant elements (also known as flexure joints) that is designed to produce a geometrically well-defined motion upon application of a force.

Machine elements[edit]

The elementary mechanical components of a machine are termed machine elements. These elements consist of three basic types (i) structural components such as frame members, bearings, axles, splines, fasteners, seals, and lubricants, (ii) mechanisms that control movement in various ways such as gear trains, belt or chain drives, linkages, cam and follower systems, including brakes and clutches, and (iii) control components such as buttons, switches, indicators, sensors, actuators and computer controllers.^[60] While generally not considered to be a machine element, the shape, texture and color of covers are an important part of a machine that provide a styling and operational interface between the mechanical components of a machine and its users.

Structural components[edit]

A number of machine elements provide important structural functions such as the frame, bearings, splines, spring and seals.

• The recognition that the frame of a mechanism is an important machine element changed the name three-bar linkage into four-bar linkage. Frames are generally assembled from truss or beam elements.
• Bearings are components designed to manage the interface between moving elements and are the source of friction in machines. In general, bearings are designed for pure rotation or straight line movement.
• Splines and keys are two ways to reliably mount an axle to a wheel, pulley or gear so that torque can be transferred through the connection.
• Springs provides forces that can either hold components of a machine in place or acts as a suspension to support part of a machine.
• Seals are used between mating parts of a machine to ensure fluids, such as water, hot gases, or lubricant do not leak between the mating surfaces.
• Fasteners such as screws, bolts, spring clips, and rivets are critical to the assembly of components of a machine. Fasteners are generally considered to be removable. In contrast, joining methods, such as welding, soldering, crimping and the application of adhesives, usually require cutting the parts to disassemble the components

Controllers[edit]

Controllers combine sensors, logic, and actuators to maintain the performance of components of a machine. Perhaps the best known is the flyball governor for a steam engine. Examples of these devices range from a thermostat that as temperature rises opens a valve to cooling water to speed controllers such as the cruise control system in an automobile. The programmable logic controller replaced relays and specialized control mechanisms with a programmable computer. Servomotors that accurately position a shaft in response to an electrical command are the actuators that make robotic systems possible.

Computing machines[edit]

Charles Babbage designed machines to tabulate logarithms and other functions in 1837. His Difference engine can be considered an advanced mechanical calculator and his Analytical Engine a forerunner of the modern computer, though none of the larger designs were completed in Babbage’s lifetime.

The Arithmometer and the Comptometer are mechanical computers that are precursors to modern digital computers. Models used to study modern computers are termed State machine and Turing machine.

Molecular machines[edit]

The biological molecule myosin reacts to ATP and ADP to alternately engage with an actin filament and change its shape in a way that exerts a force, and then disengage to reset its shape, or conformation. This acts as the molecular drive that causes muscle contraction. Similarly the biological molecule kinesin has two sections that alternately engage and disengage with microtubules causing the molecule to move along the microtubule and transport vesicles within the cell, and dynein, which moves cargo inside cells towards the nucleus and produces the axonemal beating of motile cilia and flagella. «In effect, the motile cilium is a nanomachine composed of perhaps over 600 proteins in molecular complexes, many of which also function independently as nanomachines. Flexible linkers allow the mobile protein domains connected by them to recruit their binding partners and induce long-range allostery via protein domain dynamics. «^[61] Other biological machines are responsible for energy production, for example ATP synthase which harnesses energy from proton gradients across membranes to drive a turbine-like motion used to synthesise ATP, the energy currency of a cell.^[62] Still other machines are responsible for gene expression, including DNA polymerases for replicating DNA,^{[citation needed]} RNA polymerases for producing mRNA,^{[citation needed]} the spliceosome for removing introns, and the ribosome for synthesising proteins. These machines and their nanoscale dynamics are far more complex than any molecular machines that have yet been artificially constructed.^[63] These molecules are increasingly considered to be nanomachines.^{[citation needed]}

Researchers have used DNA to construct nano-dimensioned four-bar linkages.^[64][65]

Impact[edit]

Mechanization and automation[edit]

Mechanization or mechanisation (BE) is providing human operators with machinery that assists them with the muscular requirements of work or displaces muscular work. In some fields, mechanization includes the use of hand tools. In modern usage, such as in engineering or economics, mechanization implies machinery more complex than hand tools and would not include simple devices such as an un-geared horse or donkey mill. Devices that cause speed changes or changes to or from reciprocating to rotary motion, using means such as gears, pulleys or sheaves and belts, shafts, cams and cranks, usually are considered machines. After electrification, when most small machinery was no longer hand powered, mechanization was synonymous with motorized machines.^[66]

Automation is the use of control systems and information technologies to reduce the need for human work in the production of goods and services. In the scope of industrialization, automation is a step beyond mechanization. Whereas mechanization provides human operators with machinery to assist them with the muscular requirements of work, automation greatly decreases the need for human sensory and mental requirements as well. Automation plays an increasingly important role in the world economy and in daily experience.

Automata[edit]

An automaton (plural: automata or automatons) is a self-operating machine. The word is sometimes used to describe a robot, more specifically an autonomous robot. A Toy Automaton was patented in 1863.^[67]

Mechanics[edit]

Usher^[68] reports that Hero of Alexandria’s treatise on Mechanics focussed on the study of lifting heavy weights. Today mechanics refers to the mathematical analysis of the forces and movement of a mechanical system, and consists of the study of the kinematics and dynamics of these systems.

Dynamics of machines[edit]

The dynamic analysis of machines begins with a rigid-body model to determine reactions at the bearings, at which point the elasticity effects are included. The rigid-body dynamics studies the movement of systems of interconnected bodies under the action of external forces. The assumption that the bodies are rigid, which means that they do not deform under the action of applied forces, simplifies the analysis by reducing the parameters that describe the configuration of the system to the translation and rotation of reference frames attached to each body.^[69][70]

The dynamics of a rigid body system is defined by its equations of motion, which are derived using either Newtons laws of motion or Lagrangian mechanics. The solution of these equations of motion defines how the configuration of the system of rigid bodies changes as a function of time. The formulation and solution of rigid body dynamics is an important tool in the computer simulation of mechanical systems.

Kinematics of machines[edit]

The dynamic analysis of a machine requires the determination of the movement, or kinematics, of its component parts, known as kinematic analysis. The assumption that the system is an assembly of rigid components allows rotational and translational movement to be modeled mathematically as Euclidean, or rigid, transformations. This allows the position, velocity and acceleration of all points in a component to be determined from these properties for a reference point, and the angular position, angular velocity and angular acceleration of the component.

Machine design[edit]

Machine design refers to the procedures and techniques used to address the three phases of a machine’s lifecycle:

1. invention, which involves the identification of a need, development of requirements, concept generation, prototype development, manufacturing, and verification testing;
2. performance engineering involves enhancing manufacturing efficiency, reducing service and maintenance demands, adding features and improving effectiveness, and validation testing;
3. recycle is the decommissioning and disposal phase and includes recovery and reuse of materials and components.

See also[edit]

• Automaton
• Gear train
• History of technology
• Linkage (mechanical)
• List of mechanical, electrical and electronic equipment manufacturing companies by revenue
• Mechanism (engineering)
• Mechanical advantage
• Outline of automation
• Outline of machines
• Power (physics)
• Simple machines
• Technology
• Virtual work
• Work (physics)

References[edit]

Further reading[edit]

• Oberg, Erik; Franklin D. Jones; Holbrook L. Horton; Henry H. Ryffel (2000). Christopher J. McCauley; Riccardo Heald; Muhammed Iqbal Hussain (eds.). Machinery’s Handbook (26th ed.). New York: Industrial Press Inc. ISBN 978-0-8311-2635-3.
• Reuleaux, Franz (1876). The Kinematics of Machinery. Trans. and annotated by A. B. W. Kennedy. New York: reprinted by Dover (1963).
• Uicker, J. J.; G. R. Pennock; J. E. Shigley (2003). Theory of Machines and Mechanisms. New York: Oxford University Press.

• Oberg, Erik; Franklin D. Jones; Holbrook L. Horton; Henry H. Ryffel (2000). Christopher J. McCauley; Riccardo Heald; Muhammed Iqbal Hussain (eds.). Machinery’s Handbook (30th ed.). New York: Industrial Press Inc. ISBN 9780831130992.

External links[edit]

This article is about devices that perform tasks.

The scientific definition of a machine is any device that transmits or modifies energy. In common usage, the meaning is restricted to devices having rigid moving parts that perform or assist in performing some work. Machines normally require some energy source («input») and always accomplish some sort of work («output»). Devices with no rigid moving parts are commonly considered tools, or simply devices, not machines.

People have used mechanisms to amplify their abilities since before written records were available. Generally these devices decrease the amount of force required to do a given amount of work, alter the direction of the force, or transform one form of motion or energy into another.

Modern power tools, automated machine tools, and human-operated power machinery are tools that are also machines. Machines used to transform heat or other energy into mechanical energy are known as engines.

Hydraulics devices may also be used to support industrial applications, although devices entirely lacking rigid moving parts are not commonly considered machines. Hydraulics are widely used in heavy equipment industries, automobile industries, marine industries, aeronautical industries, construction equipment industries, and earthmoving equipment industries.

History

Perhaps the first example of a human made device designed to manage power is the hand axe, made by chipping flint to form a wedge. A wedge is a simple machine that transforms lateral force and movement of the tool into a transverse splitting force and movement of the workpiece.

The idea of a simple machine originated with the Greek philosopher Archimedes around the third century B.C.E., who studied the Archimedean simple machines: lever, pulley, and screw. However the Greeks’ understanding was limited to statics (the balance of forces) and did not include dynamics (the tradeoff between force and distance) or the concept of work.

During the Renaissance the dynamics of the Mechanical Powers, as the simple machines were called, began to be studied from the standpoint of how much useful work they could perform, leading eventually to the new concept of mechanical work. In 1586 Flemish engineer Simon Stevin derived the mechanical advantage of the inclined plane, and it was included with the other simple machines. The complete dynamic theory of simple machines was worked out by Italian scientist Galileo Galilei in 1600 in Le Meccaniche («On Mechanics»). He was the first to understand that simple machines do not create energy, they merely transform it.

The classic rules of sliding friction in machines were discovered by Leonardo da Vinci (1452–1519), but remained unpublished in his notebooks. They were rediscovered by Guillaume Amontons (1699) and were further developed by Charles-Augustin de Coulomb (1785).

Impact

Industrial Revolution

The Industrial Revolution was a period from 1750 to 1850 where changes in agriculture, manufacturing, mining, transportation, and technology had a profound effect on the social, economic, and cultural conditions of the times. It began in the United Kingdom, then subsequently spread throughout Western Europe, North America, Japan, and eventually the rest of the world.

Starting in the later part of the eighteenth century, there began a transition in parts of Great Britain’s previously manual labor and draft-animal–based economy towards machine-based manufacturing. It started with the mechanization of the textile industries, the development of iron-making techniques and the increased use of refined coal.

Mechanization and automation

Mechanization is providing human operators with machinery that assists them with the muscular requirements of work or displaces muscular work. In some fields, mechanization includes the use of hand tools. In modern usage, such as in engineering or economics, mechanization implies machinery more complex than hand tools and would not include simple devices such as an un-geared horse or donkey mill. Devices that cause speed changes or changes to or from reciprocating to rotary motion, using means such as gears, pulleys or sheaves and belts, shafts, cams and cranks, usually are considered machines. After electrification, when most small machinery was no longer hand powered, mechanization was synonymous with motorized machines.

Automation is the use of control systems and information technologies to reduce the need for human work in the production of goods and services. In the scope of industrialization, automation is a step beyond mechanization. Whereas mechanization provides human operators with machinery to assist them with the muscular requirements of work, automation greatly decreases the need for human sensory and mental requirements as well. Automation plays an increasingly important role in the world economy and in daily experience.

Automata

An automaton (plural: automata or automatons) is a self-operating machine. The word is sometimes used to describe a robot, more specifically an autonomous robot.

Types

The mechanical advantage of a simple machine is the ratio between the force it exerts on the load and the input force applied. This does not entirely describe the machine’s performance, as force is required to overcome friction as well. The mechanical efficiency of a machine is the ratio of the actual mechanical advantage (AMA) to the ideal mechanical advantage (IMA). Functioning physical machines are always less than 100 percent efficient.

Mechanical

The word mechanical refers to the work that has been produced by machines or the machinery. It mostly relates to the machinery tools and the mechanical applications of science. Some of its synonyms are automatic and mechanic.

Simple machines

The idea that a machine can be broken down into simple movable elements led Archimedes to define the lever, pulley and screw as simple machines. By the time of the Renaissance this list increased to include the wheel and axle, wedge and inclined plane.

Engines

An engine or motor is a machine designed to convert energy into useful mechanical motion. Heat engines, including internal combustion engines and external combustion engines (such as steam engines) burn a fuel to create heat, which is then used to create motion. Electric motors convert electrical energy into mechanical motion, pneumatic motors use compressed air and others, such as wind-up toys use elastic energy. In biological systems, molecular motors like myosins in muscles use chemical energy to create motion.

Electrical

Electrical means operating by or producing electricity, relating to or concerned with electricity. In other words, it means using, providing, producing, transmitting or operated by electricity.

Electrical machine

An electrical machine is the generic name for a device that converts mechanical energy to electrical energy, converts electrical energy to mechanical energy, or changes alternating current from one voltage level to a different voltage level.

Electronic machine

Electronics is the branch of physics, engineering and technology dealing with electrical circuits that involve active electrical components such as vacuum tubes, transistors, diodes and integrated circuits, and associated passive interconnection technologies. The nonlinear behavior of active components and their ability to control electron flows makes amplification of weak signals possible and is usually applied to information and signal processing. Similarly, the ability of electronic devices to act as switches makes digital information processing possible. Interconnection technologies such as circuit boards, electronic packaging technology, and other varied forms of communication infrastructure complete circuit functionality and transform the mixed components into a working system.

Computing machines

Computers are machines to process information, often in the form of numbers. Charles Babbage designed various machines to tabulate logarithms and other functions in 1837. His Difference engine can be considered an advanced mechanical calculator and his Analytical Engine a forerunner of the modern computer, though none were built in Babbage’s lifetime.

Modern computers are electronic ones. They use electric charge, current or magnetization to store and manipulate information. Computer architecture deals with detailed design of computers. There are also simplified models of computers, like State machine and Turing machine.

Molecular machines

Study of the molecules and proteins that are the basis of biological functions has led to the concept of a molecular machine. For example, current models of the operation of the kinesin molecule that transports vesicles inside the cell as well as the myosin molecule that operates against actin to cause muscle contraction; these molecules control movement in response to chemical stimuli.

Researchers in nano-technology are working to construct molecules that perform movement in response to a specific stimulus. In contrast to molecules such as kinesin and myosin, these nanomachines or molecular machines are constructions like traditional machines that are designed to perform in a task.

Types of machines and related components

Classification	Machine(s)
Simple machines	Inclined plane, Wheel and axle, Lever, Pulley, Wedge, Screw
Mechanical components	Axle, Bearings, Belts, Bucket, Fastener, Gear, Key, Link chains, Rack and pinion, Roller chains, Rope, Seals, Spring, Wheel
Clock	Atomic clock, Watch, Pendulum clock, Quartz clock
Compressors and Pumps	Archimedes’ screw, Eductor-jet pump, Hydraulic ram, Pump, Trompe, Vacuum pump
Heat engines	External combustion engines	Steam engine, Stirling engine
Internal combustion engines	Reciprocating engine, Gas turbine
Heat pumps	Absorption refrigerator, Thermoelectric refrigerator, Regenerative cooling
Linkages	Pantograph, Cam, Peaucellier-Lipkin
Turbine	Gas turbine, Jet engine, Steam turbine, Water turbine, Wind generator, Windmill
Aerofoil	Sail, Wing, Rudder, Flap, Propeller
Information technology	Computer, Calculator, Telecommunications networks
Electricity	Vacuum tube, Transistor, Diode, Resistor, Capacitor, Inductor, Memristor, Semiconductor
Robots	Actuator, Servo, Servomechanism, Stepper motor
Miscellaneous	Vending machine, Wind tunnel, Check weighing machines, Riveting machines

Machine elements

Machines are assembled from standardized types of components. These elements consist of mechanisms that control movement in various ways such as gear trains, transistor switches, belt or chain drives, linkages, cam and follower systems, brakes and clutches, and structural components such as frame members and fasteners.

Modern machines include sensors, actuators and computer controllers. The shape, texture and color of covers provide a styling and operational interface between the mechanical components of a machine and its users.

Mechanisms

Assemblies within a machine that control movement are often called «mechanisms.» Mechanisms are generally classified as gears and gear trains, cam and follower mechanisms, and linkages, though there are other special mechanisms such as clamping linkages, indexing mechanisms and friction devices such as brakes and clutches.

Controllers

Controllers combine sensors, logic, and actuators to maintain the performance of components of a machine. Perhaps the best known is the flyball governor for a steam engine. Examples of these devices range from a thermostat that as temperature rises opens a valve to cooling water to speed controllers such the cruise control system in an automobile. The programmable logic controller replaced relays and specialized control mechanisms with a programmable computer. Servo motors that accurately position a shaft in response to an electrical command are the actuators that make robotic systems possible.

References

ISBN links support NWE through referral fees

• Boothroyd, Geoffrey and Winston A. Knight. 2005. Fundamentals of Machining and Machine Tools, Third Edition (Mechanical Engineering (Marcell Dekker)). Boca Raton, FL: CRC. ISBN 1574446592
• Myszka, David H. 1998. Machines and Mechanisms: Applied Kinematic Analysis. Upper Saddle River, NJ: Prentice Hall. ISBN 0135979153
• Oberg, Erik, Franklin D. Jones, Holbrook L. Horton, and Henry H. Ryffel. 2000. Machinery’s Handbook. New York, NY: Industrial Press Inc. ISBN 0831126353
• Uicker, John, Gordon Pennock, and Joseph Shigley. Theory of Machines and Mechanisms. Oxford University Press, 2010. ISBN 978-0195371239
• Usher, Abbott Payson. A History of Mechanical Inventions. Dover Publications, 2011. ISBN 978-0486255934

External links

All links retrieved November 5, 2022.

• 21 Jobs Lost to Automation Statistics for 2020